Kinetic mechanism of glycogen phosphorylase. As this enzyme is now available in purified form, it is possible to generate kinetic data needed for a detailed analysis of its role in the control of glycogen metabolism. Utilizing a kinetic analysis based on initial velocities, inhibitor studies, and isotope exchange measurements, Engers et al. (Canadian J. of Biochem. 1970, 48:746-754) have proposed an ordered Bi-Bi mechanism for rabbit muscle phosphorylase a. At this point, a detailed kinetic study has not been reported for a phosphorylase purified from other than a mammalian source. This would be of interest as all information to date indicates that the active slime mold phosphorylase exists in only one form (configuration). Trehalose-6-phosphate synthetase. Procedures will be developed using differential centrifugation and sucrose density gradient analysis for the isolation of that structure with which latent T-6-P synthetase is associated. Investigations will also be directed towards developing methods for unmasking the organelle-associated enzyme, for example, by using phospholipase, proteolytic enzymes, chaotropic salts, etc. Trehalase will be purified to homogeneity from vegetative amoebae and mature sorocarps using techniques such as ethanol fractionation, G200 Sephadex chromatography and differential elution by trehalose during ion-exchange chromatography on GAE-Sephadex. Preliminary data indicate that two species of trehalase exist in soro-sorocarbs & only 1 in amoebae. Both types will be kinetically characterized.